if your TV is configured with DHCP to get its IP-address you have to look i your DHCP-Servers lease table to find the current IP of it.
the following init script creates an empty mp3 file in your virtual usb drive whose name is the current IP

maybe there is a way to create a still empty but valid mp3 file
or find any already existing mp3 file in firmware image and copy that to a tmpfs location
and put even more info in id3 tags that should be viewable with media player